The wife of famed math genius John Nash Jr. recently worried that she and her Nobel Prize-winning husband might suddenly die, leaving their mentally ill son without their support, a close pal said Monday.

“She was worried, because they were aging, that at some point, they wouldn’t be around forever, and they were worried about the well-being of their son,” Wentz said.

The couple’s child, John “Johnny” Charles Nash, 56, suffers from schizophrenia, the same mental disorder that plagued his father. Professor Nash’s struggle with the disease was chronicled in the Oscar-winning movie “A Beautiful Mind,” in which he was played by Russell Crowe.

Johnny, who lives in his parents’ West Windsor, NJ, home, and Nash’s other son, John Stier of Lynn, Mass., are still shocked by their famous father’s sudden death, Wentz said.

“[Johnny] just needs some time and space, and it is a shock, but he’s dealing with it well,” she said outside the family’s house. “Their other son is also very upset.”

The taxi that Professor John Nash was in when it crashed on the New Jersey Turnpike.G.N. Miller

John, 86, and Alicia, 82, were heading home from Newark Airport when their taxi crashed into a guardrail in Monroe Township.

The Princeton University professor and his wife had just returned from a trip to Norway, where John and NYU mathematician Louis Nirenberg received the Abel Prize for Mathematics.

Their flight arrived five hours early Saturday, so the Nashes decided to take a taxi home instead of the limo they’d scheduled to pick them up.

“The week was so beautiful,” Nirenberg told The Post on Monday. “It was a very full week.”

He added that people were looking in on the Nashes’ son while they were away.

“I asked why they didn’t just call, and they said he doesn’t answer the phone,” Nirenberg said.

A funeral service for the couple will be held at Mather-Hodge Funeral Home in Princeton in the coming days.

“Everything is tentative, and it will be private, and I assume there will be a memorial service for the public,” Wentz said.

A spokesman for the Middlesex County Prosecutor’s Office said no charges are expected to be filed against the cab’s driver, Tark Girgis, according to NJ.com.

The cabby was trying to pass another car in the center lane of the Turnpike when he lost control and careened into a guardrail near Interchange 8A, police said. As The Post reported Monday, Girgis had been on the job for only two weeks.

The New Jersey State Police said the Nashes weren’t wearing seat belts at the time of the accident.